Sydney gang leader again a court no-show

Sydney's notorious gangland siblings the Qaumi brothers are due to return to court for the second day in a row to face a sentence hearing over a string of brutal shootings.

Brothers 4 Life Blacktown chapter leader Farhad Qaumi, 34, and his brothers Mumtaz, 32, and Jamil, 25, face lengthy prison terms for their key roles in the violence, which erupted in western Sydney in late 2013.

Only Mumtaz and Jamil were in court on Thursday for the first proper day of an extended hearing in the NSW Supreme Court.

Farhad's barrister John Stratton SC said the gang leader was concerned he'd act in a way the judge would find disrespectful, and had instructed "in strong terms" that he didn't wish to attend on both days.

The shootings for which the brothers will be sentenced include the December 2013 hit on debt collector Joseph Antoun at Strathfield, for which Farhad and Mumtaz Qaumi were convicted of murder.

There is also the October 2013 gunning down of Mahmoud Hamzy at Revesby Heights, over which all three brothers were found guilty of manslaughter.